Yotanwa is absolutely the real deal, but Rinshoujou has phenomenal portrayal.
It's hard to compare their leadership capabilities because Yotanwa is also a king in addition to the mountain tribe's top military commander. Rinshoujou having 10 subordinate vassals under him is crazy and he shouldn't be underestimated.
Overall it's hard to compare them because we never saw Rinshoujou in action, but i'm not sure if any solo great general could beat 100k mountain lads lol
As far leadership goes, I don't think there is anything to discuss.
RSJ bought and raised Gyou'un and CGR, he was their master from the beginning of their relationship. We don't know what the case was with the rest of the Ten Heroes, but we can reasonably assume his nobility, station and status all played a big role.
The mountainfolk don't give a shit who your daddy was or how much money you got, and yet Yo Tan Wa, a
woman, is taken for
king and deified as
Lord of Death by like a hundred clans of former enemies that now fight alongside each other for her cause.
Granted, there wasn't much of a choice in the mountainfolk being conquered, but there absolutely is in way they respond to her leadership, and these mfers have religious experiences when she speaks to them.
RSJ was smarter and likely better at strategy, and likely even had a deeper bag in terms of tactics, but YTW isn't lacking in any department, and pretty much no one can compete with her as a leader - aside from maybe Ri Boku, a hero to soldiers and commonfolk alike, whose greatest strength and weapon is empathy.